Ac-SDKP通过Gα_s/Gα_i-cAMP信号通路抑制矽肺大鼠肺纤维化  

Effect and mechanism of Ac-SDKP on inhibition of silicosis via Gα_s/Gα_i-cAMP pathway

作　　者：耿玉聪 李红垒 高学敏 李世峰 薛新新 杨奕 徐丁洁 徐洪 杨方 

机构地区：[1]华北理工大学医学实验研究中心,河北唐山063000 [2]华北理工大学中医学院,河北唐山063000

出　　处：《东南大学学报（医学版）》2016年第5期658-663,共6页Journal of Southeast University(Medical Science Edition)

基　　金：国家自然科学基金资助项目(81472953);河北省自然科学基金资助项目(H201409115);河北省研究生创新项目(2015S04)

摘　　要：目的:研究N-乙酰基-丝氨酰-天门冬氨酰-赖氨酰-脯氨酸(Ac-SDKP)与激动型G蛋白(Gαs)/抑制型G蛋白(Gαi)-环磷酸腺苷(c AMP)信号通路的关系,探讨Ac-SDKP抑制矽肺大鼠纤维化的作用及其机制。方法:采用一次性支气管灌注Si O2构建大鼠矽肺模型,并予以Ac-SDKP抗纤维化治疗和预防治疗。体外采用血管紧张素(Ang)Ⅱ诱导大鼠肺成纤维细胞向肌成纤维细胞分化,并予以Ac-SDKP、缬沙坦(valasrtan)和二丁酰环磷酸腺苷(db-c AMP)预处理。免疫荧光法检测Gαs蛋白与波形蛋白(vimentin)在矽肺组织中的定位与表达,Western blot法检测矽肺组织和AngⅡ诱导的肌成纤维细胞中Gαs、Gαi、α-平滑肌肌动蛋白(SMA)和Ⅰ型胶原表达,EIA试剂盒检测c AMP活性。结果:与对照组相比,矽肺大鼠肺组织中Gαs和c AMP表达下调,而Gαi表达上调并伴随α-SMA和Ⅰ型胶原表达升高(P<0.05),Ac-SDKP抗纤维化治疗和预防治疗均可抑制该变化;同时体外研究发现Ac-SDKP、valsartan和db-c AMP预处理后可抑制AngⅡ介导的Gαs和c AMP表达下调(P<0.05),抑制肌成纤维细胞分化和细胞外基质沉积。结论:Ac-SDKP通过调节Gαs/Gαi-c AMP信号抑制肌成纤维细胞分化,发挥抗矽肺大鼠肺纤维化的作用。Objective： To explore the anti-fibrotic effect of Ac-SDKP via Gαs/ Gαi-c AMP pathway in silicotic rats. Methods： Silicotic rats were constructed using bronchial instillation of Si O2,with Ac-SDKP post-treatment and pre-treatment. Myofibroblasts induced by Ang Ⅱ were pre-treated with Ac-SDKP,valsartan and db-c AMP.The distribution and co-expression of Gsαand vimentin were observed using immunofluorescence. The expression of Gαs,Gαi,α-SMA and collagen type I in lung tissue and fibroblasts were detected by Western blot. The level of c AMP was measured with EIA c AMP kit. Results： Compared with control group,the level of Gαsand c AMP were down-regulated in silicosis model,accompanied by up-regulated level of Gαi,α-SMA and collegan type I（ P〈0. 05）. Post-and pre-treatment with Ac-SDKP could suppress the changes induced by silica. In addition,AcSDKP,valsartan and db-c AMP efficiently ameliorated the down- regulation of Gαsand c AMP,myofibroblasts differentiation and collagen deposition in fibroblasts induced by Ang Ⅱ（ P〈0. 05）. Conclusion： Ac-SDKP inhibits silicosis and myofibroblasts differentiation by regulating Gαs/ Gαi-c AMP signal pathway.

关 键 词：矽肺 肌成纤维细胞 N-乙酰基-丝氨酰-天门冬氨酰-赖氨酰-脯氨酸 肺纤维化 环磷酸腺苷 大鼠 

分 类 号：R135.2[医药卫生—劳动卫生] R-332[医药卫生—公共卫生与预防医学]